Mitochondrial DNA content and mass increase in progression from normal to hyperplastic to cancer endometrium.

BACKGROUND: An increase in mitochondrial DNA (mtDNA) content and mitochondrial biogenesis associated with the activation of PGC-1α signalling pathway was previously reported in type I endometrial cancer. The aim of this study has been to evaluate if mtDNA content and the citrate synthase (CS) activity, an enzyme marker of mitochondrial mass, increase in progression from control endometrium to hyperplasia to type I endometrial carcinoma. RESULTS: Given that no statistically significant change in mtDNA content and CS activity in endometrium taken from different phases of the menstrual cycle or in menopause was found, these samples were used as control. Our research shows, for the first time, that mtDNA content and citrate synthase activity increase in hyperplastic endometrium compared to control tissues, even if their levels remain lower compared to cancer tissue. In particular, mtDNA content increases seem to precede increases in CS activity. No statistically significant change in mtDNA content and in CS activity was found in relation to different histopathological conditions such as grade, myometrial invasion and stage. CONCLUSION: MtDNA content and citrate synthase activity increases in pre-malignant lesions could be a potential molecular marker for progression from hyperplasia to carcinoma.

Oocyte morphological abnormalities in overweight women undergoing in vitro fertilization cycles.

The effect of elevated body mass index (BMI) on the oocyte quality was investigated in women undergoing in vitro fertilization (IVF) cycles. A total of 268 patients classified on the basis of BMI subject to the first reproductive treatment were included in this study: the normal weight (NW) group consisted of 160 patients with BMI 19-24.9 kg/m(2) and the overweight (OW) group consisted of 108 patients with BMI ≥ 25 kg/m(2). All women were treated with a standard long luteal protocol. The oocyte features were classified as extracytoplasmic or cytoplasmic abnormalities. Outcomes were oocyte morphology, embryo quality, fertilization and implantation rates, and the ovarian response to stimulation. A higher percentage of oocytes with granular cytoplasm was found in women with BMI ≥ 25 (p = 0.04). However, percentages of mature, immature oocytes and germinal vesicle were similar in both groups. No differences were found in fertilization and cleavage rates and percentages of embryo quality. The implantation rate (p < 0.001) was significantly lower in the OW group than in the NW group. The amount of gonadotrophins was significantly higher in OW group (p = 0.003). These findings suggest that the poor reproductive outcome of obese women is influenced by the release of ova with reduced fertilization potential.